The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Australia.
The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Australia; Division of Sleep Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Sleep Med. 2014 Jan;15(1):83-90. doi: 10.1016/j.sleep.2013.09.011. Epub 2013 Oct 14.
In adults sleep-disordered breathing (SDB) has been associated with impaired baroreflex control of blood pressure (BP), which has been linked to increased cardiovascular morbidity. In children, the long-term effects of SDB on baroreflex sensitivity (BRS) and BP variability (BPV) are unknown.
Children previously diagnosed with SDB (n=40) and 20 nonsnoring controls aged 11-16 y underwent overnight polysomnography with continuous BP measurement, four years after the original diagnosis. At follow-up, SDB was categorized as resolved (absence of snoring and obstructive apnea hypopnea index (OAHI)≤1) or unresolved (continued to snore or had an OAHI>1). BRS and BPV were calculated using cross-spectral analysis and power spectral analysis, respectively.
Only children with resolved obstructive sleep apnea (OSA) at follow-up demonstrated an increase in BRS from 9.7±3 (ms mmHg(-1)) at baseline to 11.8±4 (ms mmHg(-1)) at follow-up (P=.03). However, children with all severities of both resolved and unresolved SDB showed a significant decrease in BPV from baseline to follow-up (a decrease in total power BPV (P<.05) and a shift in BPV spectra away from respiratory-related frequencies (increased low-frequency/high-frequency [LF/HF] ratio, P<.01). The change in OAHI was the sole determinant of change in BRS, HF power, and LF/HF ratio.
Improvement in SDB was associated with improved BP control, regardless if SDB was treated or spontaneously resolved four years after initial diagnosis. Our findings highlight the importance of monitoring children to ensure improvement of SDB and reduce the risk for cardiovascular morbidity in the future.
在成年人中，睡眠呼吸障碍（SDB）与血压（BP）的压力反射控制受损有关，而血压反射控制受损与心血管发病率增加有关。在儿童中，SDB 对压力反射敏感性（BRS）和血压变异性（BPV）的长期影响尚不清楚。
40 名先前被诊断为 SDB 的儿童和 20 名年龄在 11-16 岁、不打鼾的对照者在最初诊断四年后接受了一整夜的多导睡眠图和连续血压测量。在随访时，SDB 分为已解决（无打鼾和阻塞性睡眠呼吸暂停低通气指数（OAHI）≤1）或未解决（持续打鼾或 OAHI>1）。BRS 和 BPV 分别使用交叉谱分析和功率谱分析来计算。
只有在随访时阻塞性睡眠呼吸暂停（OSA）得到解决的儿童，BRS 从基线时的 9.7±3（ms mmHg(-1))增加到随访时的 11.8±4（ms mmHg(-1))（P=.03）。然而，所有严重程度的已解决和未解决的 SDB 儿童的 BPV 均从基线到随访时显著降低（总功率 BPV 降低（P<.05），BPV 谱向呼吸相关频率转移（低频/高频比增加（LF/HF），P<.01）。OAHI 的变化是 BRS、HF 功率和 LF/HF 比变化的唯一决定因素。
SDB 的改善与血压控制的改善有关，无论 SDB 是否在最初诊断四年后得到治疗或自然缓解。我们的研究结果强调了监测儿童的重要性，以确保 SDB 的改善，并降低未来心血管发病率的风险。
